CVE-2026-66034

libssh2 through 1.11.1, fixed in commit a13bb6c, contains a missing bounds check vulnerability that allows a malicious SSH server to trigger an arbitrary-length heap out-of-bounds read and a free of an uninitialized pointer via the publickey subsystem. In libssh2publickeylistfetch, the version 1...

AZL-93396 CVE-2026-66032 affecting package libssh2 for versions less than 1.11.1-5

libssh2 through 1.11.1, fixed in commit 5e47761, contains a double-free vulnerability in the sftpopen function in src/sftp.c that allows a malicious SSH server to corrupt the heap of any authenticated client opening an SFTP session. When a server responds to SSHFXPOPEN with SSHFXPSTATUS containin...

AZL-93399 CVE-2026-66035 affecting package libssh2 for versions less than 1.11.1-5

libssh2 through 1.11.1, fixed in commit 42e33d8, contains a pre-authentication heap buffer overflow vulnerability that allows a malicious SSH server to corrupt heap metadata in any connecting client by sending a packet with a packetlength smaller than the cipher's block size during Encrypt-then-M...

DEBIAN-CVE-2026-66035

libssh2 through 1.11.1, fixed in commit 42e33d8, contains a pre-authentication heap buffer overflow vulnerability that allows a malicious SSH server to corrupt heap metadata in any connecting client by sending a packet with a packetlength smaller than the cipher's block size during Encrypt-then-M...

DEBIAN-CVE-2026-66033

libssh2 through 1.11.1, fixed in commit a2ed82d, contains a pre-authentication integer underflow vulnerability in the ssh2ciphercrypt function in src/openssl.c that allows a malicious SSH server to crash any connecting client by negotiating AES-GCM ciphers during handshake. Attackers can exploit...

DEBIAN-CVE-2026-66034

libssh2 through 1.11.1, fixed in commit a13bb6c, contains a missing bounds check vulnerability that allows a malicious SSH server to trigger an arbitrary-length heap out-of-bounds read and a free of an uninitialized pointer via the publickey subsystem. In libssh2publickeylistfetch, the version 1...

DEBIAN-CVE-2026-66032

libssh2 through 1.11.1, fixed in commit 5e47761, contains a double-free vulnerability in the sftpopen function in src/sftp.c that allows a malicious SSH server to corrupt the heap of any authenticated client opening an SFTP session. When a server responds to SSHFXPOPEN with SSHFXPSTATUS containin...

CVE-2026-66035

libssh2 through 1.11.1, fixed in commit 42e33d8, contains a pre-authentication heap buffer overflow vulnerability that allows a malicious SSH server to corrupt heap metadata in any connecting client by sending a packet with a packetlength smaller than the cipher's block size during Encrypt-then-M...

CVE-2026-66033

libssh2 through 1.11.1, fixed in commit a2ed82d, contains a pre-authentication integer underflow vulnerability in the ssh2ciphercrypt function in src/openssl.c that allows a malicious SSH server to crash any connecting client by negotiating AES-GCM ciphers during handshake. Attackers can exploit...

AZL-97428 CVE-2026-66033 affecting package rust for versions less than 1.96.1-2

libssh2 through 1.11.1, fixed in commit a2ed82d, contains a pre-authentication integer underflow vulnerability in the ssh2ciphercrypt function in src/openssl.c that allows a malicious SSH server to crash any connecting client by negotiating AES-GCM ciphers during handshake. Attackers can exploit...

UBUNTU-CVE-2026-66032

libssh2 through 1.11.1, fixed in commit 5e47761, contains a double-free vulnerability in the sftpopen function in src/sftp.c that allows a malicious SSH server to corrupt the heap of any authenticated client opening an SFTP session. When a server responds to SSHFXPOPEN with SSHFXPSTATUS containin...

CVE-2026-66033

libssh2 through 1.11.1, fixed in commit a2ed82d, contains a pre-authentication integer underflow vulnerability in the ssh2ciphercrypt function in src/openssl.c that allows a malicious SSH server to crash any connecting client by negotiating AES-GCM ciphers during handshake. Attackers can exploit...

CVE-2026-66035

libssh2 through 1.11.1, fixed in commit 42e33d8, contains a pre-authentication heap buffer overflow vulnerability that allows a malicious SSH server to corrupt heap metadata in any connecting client by sending a packet with a packetlength smaller than the cipher's block size during Encrypt-then-M...

UBUNTU-CVE-2026-66034

libssh2 through 1.11.1, fixed in commit a13bb6c, contains a missing bounds check vulnerability that allows a malicious SSH server to trigger an arbitrary-length heap out-of-bounds read and a free of an uninitialized pointer via the publickey subsystem. In libssh2publickeylistfetch, the version 1...

CVE-2026-66034

libssh2 through 1.11.1, fixed in commit a13bb6c, contains a missing bounds check vulnerability that allows a malicious SSH server to trigger an arbitrary-length heap out-of-bounds read and a free of an uninitialized pointer via the publickey subsystem. In libssh2publickeylistfetch, the version 1...

UBUNTU-CVE-2026-66035

libssh2 through 1.11.1, fixed in commit 42e33d8, contains a pre-authentication heap buffer overflow vulnerability that allows a malicious SSH server to corrupt heap metadata in any connecting client by sending a packet with a packetlength smaller than the cipher's block size during Encrypt-then-M...

CVE-2026-66035 libssh2 Heap Buffer Overflow via ETM Cipher Negotiation

libssh2 through 1.11.1, fixed in commit 42e33d8, contains a pre-authentication heap buffer overflow vulnerability that allows a malicious SSH server to corrupt heap metadata in any connecting client by sending a packet with a packetlength smaller than the cipher's block size during Encrypt-then-M...

CVE-2026-66035

CVE-2026-66035 affects libssh2 up to 1.11.1 and was fixed in commit 42e33d8. The vulnerability is a pre-authentication heap buffer overflow in the Encrypt-then-MAC (ETM) cipher negotiation path. In libssh2’s fullpacket() implemented under src/transport.c, the ETM code path allocates a buffer of p...

EUVD-2026-48722

libssh2 through 1.11.1, fixed in commit 42e33d8, contains a pre-authentication heap buffer overflow vulnerability that allows a malicious SSH server to corrupt heap metadata in any connecting client by sending a packet with a packetlength smaller than the cipher's block size during Encrypt-then-M...

CVE-2026-66035 libssh2 Heap Buffer Overflow via ETM Cipher Negotiation

libssh2 through 1.11.1, fixed in commit 42e33d8, contains a pre-authentication heap buffer overflow vulnerability that allows a malicious SSH server to corrupt heap metadata in any connecting client by sending a packet with a packetlength smaller than the cipher's block size during Encrypt-then-M...